I have had an irregular period for as long as I can remember, but it has only been recently that I have been experiencing a dark brown vaginal discharge 2 or 3 weeks after a period.

My partner and I are trying to conceive a second child and having this discharge is making it difficult for intercourse. Approximately 2 or 3 weeks after a period I get this dark brown vaginal discharge which lasts from 2 days to 2 weeks. My cycles are irregular and in the past 5 months my cycles have been 37 days, 52 days and 51 days. I am now on cycle day 31 and have had this discharge for 8 days. I also get this discharge exactly 3 days before a period but then I have no vaginal discharges until 2 or 3 weeks after a period. I have seen doctors and have had this discharge tested and it has come back with nothing out of the ordinary but I do know that this discharge is not normal and would like any advice on what this could possibly be...

I would appreciate any advice thank you, however I am going to see a Doctor on Monday...